A variety of products includes an array of individual devices on a substrate, with the devices addressable or controllable by circuitry on the substrate. For example, some display screens include an array of individually controllable pixels. In the case of light-emitting diode (LED) panels, these individual pixels can be independently controllable LEDs. The LED panels are commonly used for display screens, such as computers, touch panel devices, personal digital assistants (PDAs), cell phones, television monitors, and the like.
In general, micro-devices can be fabricated using a sequence of microfabrication techniques, such as deposition, lithography and etching, to deposit and pattern a sequence of layers. One approach for fabricating a device that includes an array of individual micro-devices is to directly fabricate the individual micro-devices on the substrate which will form part of the product. This technique has been used, e.g., to fabricate the individual micro-devices on the substrate which will form part of the product. This technique has been used, e.g., to fabricate the TFT panel and color filter panels of an active matrix liquid crystal display (LCD). However, in LED panels are difficult to manufacture in curved or bendable display.
An alternative approach for fabricating a device that includes an array of individual micro-devices is to fabricate the micro-devices en masse on a separate substrate, and then transfer the micro-devices to the substrate which will form part of the product.